Adult Echocardiography Practice Exam

M-mode tracing of a bicuspid aortic valve will demonstrate:

1. eccentric diastolic closure line of aortic valve leaflets

2. eccentric diastolic opening of aortic valve leaflets

3. eccentric systolic opening of aortic valve leaflets

4. eccentric systolic closure of aortic valve leaflets

The correct answer is: eccentric diastolic closure line of aortic valve leaflets

M-mode echocardiography provides a way to visualize the motion of the heart structures over time, and when examining a bicuspid aortic valve, distinctive patterns can be observed. In the case of a bicuspid aortic valve, the aortic valve's leaflets do not open and close symmetrically due to their malformation. The correct representation in M-mode for a bicuspid aortic valve is characterized by an eccentric diastolic closure line of the aortic valve leaflets. This means that when the heart is in diastole (the phase when the heart relaxes and fills with blood), the closure line—which represents the position where the valve leaflets come together—is not centered but rather displaced to one side. This eccentric closure occurs because the bicuspid valve has only two leaflets instead of the typical three, leading to a disruption in normal valve dynamics. The nature of this echocardiographic finding is critical as it signals the structural abnormality of the valve. Not only does the presence of a bicuspid aortic valve put a patient at risk for conditions such as aortic stenosis or regurgitation later in life, but it also helps clinicians in diagnosing the underlying valve pathology through the visualization